SLA and quality of service for Cloud Computing

Cloud Computing is a paradigm for enabling remote, on-demand access to a set of configurable computing resources. This model aims to provide hardware and software services to customers, while minimizing human efforts in terms of service installation, configuration and maintenance, for both cloud provider and cloud customer. A cloud may have the form of an Infrastructure as a Service (IaaS), a Platform as a Service (PaaS) or a Software as a Service (SaaS). However, cloud’s ad-hoc management in terms of quality-of-service and service level agreement (SLA) poses significant challenges to the performance, availability, energy consumption and economical costs of the cloud. We believe that a differentiating element between Cloud Computing environments will be the quality-of-service and the service level agreement (SLA) provided by the cloud.

The objective of the MyCloud project is to define and implement a novel cloud model: SLAaaS (SLA aware Service). The SLAaaS model enriches the general paradigm of Cloud Computing, and enables systematic and transparent integration of service levels and SLA to the cloud. SLAaaS is orthogonal to IaaS, PaaS and SaaS clouds and may apply to any of them. The MyCloud project takes into account both the cloud provider and cloud customer points of view. From cloud provider’s point of view, MyCloud proposes autonomic SLA management to handle performance, availability, energy and cost issues in the cloud. An innovative approach combines control theory techniques with distributed algorithms and language support in order to build autonomic elastic clouds. Novel models, control laws, distributed algorithms and languages will be proposed for automated provisioning, configuration and deployment of cloud services to meet SLA requirements, while tackling scalability and dynamics issues. On the other hand from cloud customer’s point of view, the MyCloud project provides SLA governance. It allows cloud customers to be part of the loop and to ba automatically notified about the state of the cloud, such as SLA violation and cloud energy consumption. The former provides more transparecy about SLA guaranties, and the latter aims to raise customers’ awareness about cloud’s energy footprint.

Two use cases are considered in the MyCloud project, both are proposed by industrial partners of the project and reflect real usage of the cloud. The first use case is related to a SaaS cloud that is autonomously elastic in order to meet performance requirements and scale with cloud usage. The second use case aims to reduce energy usage in the cloud and to notify cloud customers about cloud’s energy footprint.

MyCloud is a three-year project funded by the French National Agency for Research (ANR), starting November 2010.